Color materials used as toner for electrophotography are generally one of four colors, which are yellow, magenta, cyan, and black. Today, new toner materials are in demand for various purposes such as cards, pamphlets, and direct mails.
One type of toner contains a material that neutralizes an odor produced during an image forming process. Because such a material is used, it is difficult to differentiate an image formed with such a toner and an image formed with conventional toner.